LeetCode Solutions/Problems/771. Jewels and Stones.java
class Solution {
    public int numJewelsInStones(String jewels, String stones) {
        int result = 0;
        for (int i=0; i<stones.length(); i++){
            if (jewels.indexOf(stones.charAt(i)) != -1){
                result++;
            }
        }
        return result;
    }
}